1. Field of the Invention
The present invention relates to delivery devices or vehicles for use in the delivery of paper during the first stage of delivery of a printing press. More specifically, the invention is primarily intended for use on the first stage delivery of paper on a web offset printing press delivery table wherein the invention substantially improves performance of the web offset printing press delivery table and substantially eliminates paper jamming while increasing safety of operations.
2. Description of the Prior Art
In the art of printing press delivery tables, particularly web offset printing press delivery tables, paper is delivered in mass quantities and at very high rates of speed and volume. After the paper has completed the printing phase of the printing process the paper is then transported to the delivery phase where the paper will be cut to a required shape, folded if necessary, separated sheet from succeeding sheet, and stacked and sorted.
Immediately prior to the delivery phase a final stage of a printed material finishing process is completed by cutting the printed paper into the required size and shape. Any necessary folding has taken place at this stage of the printing press process. The first stage of the delivery phase of the printing process then is that stage which follows the final stage of a printed material finishing process. The first stage of the delivery phase is the stage where the cut printed paper is delivered to a conveyor where the cut printed paper can then be sorted or stacked. The second -stage of the delivery process then involves the slow down and conveyance of the cut printed paper to the sorting, stacking, and other stations.
During this first stage of the delivery process a key factor is the efficient transfer of the printed paper from the cutting machine, known as a rotary trimmer, to the conveyor of the second stage. In order to deliver the cut printed paper from the rotary trimmer to the conveyor a plurality of driven rollers, or "speed-up" rollers are used to both pull and accelerate away the cut printed paper. The speed-up rollers rotate at a speed equal to and up to 25% faster than the rotation of the rotary trimmer so that the cut printed paper is accelerated away from the rotary trimmer and so that succeeding sheets of cut printed paper can "cleanly" follow leading sheets by leaving a gap between the successive sheets. When successive sheets "bunch up" after leaving the rotary cutter, then jamming can occur and can significantly decrease the efficiency of the delivery process. In addition, workers trying to prevent or clean up the jammed sheets of paper must place their hands close to the rotating rotary trimmer and can be injured.
Jamming can also occur when the sheets of cut printed paper are not properly and uniformly delivered over the speed-up rollers. Prior art devices have attempted to redress these problems, but have been unsuccessful and have created further problems for the printing press industry. One such device used in the printing press delivery art involves a five wheel device that is placed on top of the speed-up rollers to press the cut printed paper leaving the rotary trimmer onto the speed-up rollers and aid the process of accelerating the paper to the conveyor of the second stage.
However, this five-wheeled device while pressing the paper onto the speed-up rollers does not alleviate the jamming problems, rather it creates jamming problems in the area, called a nip, where the paper enters the five-wheeled device as it rides atop the speed-up rollers. In addition, the individual wheeled rollers wear out and can lose their settings because they ride directly on the high speed speed-up rollers. Settings are typically lost within a period of a week. Changing the wheels involves a timely process that can take as long as thirty minutes to perform and this time represents lost printing time and high cost. The delivery table must be stopped in order for the device to be removed from the entire mounting shaft.
In addition, because the wheel rollers are placed directly on top of the speed-up rollers, gaps between the rollers are created and cause additional paper jamming. Workers trying to change or prevent this jamming are again presented with the danger of injury due to the rotating rotary trimmer when they try to fix the problems and keep the printing press running. Furthermore, the five wheels do not cover all of the speed-up rollers and create more gaps which can lead to further jamming problems. Additionally, by use of a bolt and screw connection this device is designed to direct the angle of delivery of the paper upon leaving the device, however the device utilizes a tail kicker or kicker to "knock down" the trailing edge of a cut printed paper as it leaves the device and enters onto the conveyor of the second stage. The purpose of the kicker is to aid the stacking of the paper and to prevent further jamming. Finally, in order to make any adjustments to this fivewheeled device the user must tighten various bolt and screw connections, a process that requires fine tuning and time.
Other prior art devices created to alleviate these jamming problems involve the use of multiple-belted devices that also run on top of the speed-up rollers. These devices use belts that are around five feet in length and are complicated to fix when there is ajamming problem and workers find it harder to fix a jamming problem with these devices because of the lack of hand room. Furthermore, when a belt(s) breaks and must be changed, the printing press is almost always stopped so that two or more workers can replace the long belts. This again means machine downtime and loss of money and printing time. The longer belts also mean that there is more room for jamming during delivery
Additionally, U.S. Pat. No. 5,088,719 discloses a paper delivery mechanism for web offset printing presses. This device involves multiple belts, a braking roller, a slow down pulley, an upper high speed belt, and a low speed belt and a snubber. The device therein disclosed is a complicated arrangement. The conveying device of U.S. Pat. No. 5,496,024 is also used to transport flat printed products lying on a support formed by a driven first belt. This conveying device transports the printed products forward in a conveying channel by means of a second belt disposed above the first and the entrance region of the channel is configured to be adjustable in height in the cadence of the supplied printed products. However, this device does not teach how to change either belt if the belt needs repair and the device does not teach how to control the paper after it leaves the conveying device.
Accordingly, it is a principal object of my invention to provide an inline delivery vehicle that substantially improves performance of a first stage web offset printing press delivery table and that substantially eliminates the problem of paper jamming and thereby substantially increases the safety of operations of the delivery process.
It is a further object of my invention to provide an inline delivery vehicle that uses a belt to provide a continuum and constant uniform surface area for accelerating paper over the speed-up rollers.
It is a further object of my invention to provide an inline delivery vehicle that is less likely to lose its settings and is less likely to halt the delivery process due to maintenance.
It is a still further object of my invention to provide an inline delivery vehicle that allows for the quick, efficient means for changing and repairing the belt.
It is a further object of my invention to provide an inline delivery vehicle that allows for multiple adjustments to account for different size and types of delivered paper and different control designs.
It is a still further object of my invention to provide an inline delivery vehicle that substantially eliminates the need for a separate kicker to knock-down the trailing edge of the paper for stacking purposes.
It is a further object of my invention to provide an inline delivery vehicle that is less complicated to operate, less costly to run and which is adaptable to different delivery requirements and corresponding paper dimensions.
Other objects of my invention, as well as particular features, elements, and advantages thereof, will be elucidated in, or apparent from, the following description and the accompanying drawing figures.